As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON SELECTING LANDING GEAR HANDLE TO THE DOWN POSITION, GEAR HANDLE ANNUNCIATOR REMAINED RED WITH NO GREEN LIGHT INDICATIONS. MANUAL LANDING GEAR EXTENSION WAS PERFORMED. LANDING WAS UNEVENTFUL. MAINTENANCE TROUBLESHOT THE DISCREPANCY TO A RELAY CARD THAT WAS NOT SECURE. SECURED THE RELAY CARD. SYSTEM OPS CHECKED AND A SUCCESSFUL CREW OCF WAS PERFORMED. AIRCRAFT WAS RETURNED TO SERVICE.